JP2524066Y2 - Power eased equipment for diesel cars - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a power tard device for a diesel vehicle.

[Conventional technology]

In a large truck or the like powered by a four-cycle diesel engine, a third valve-synchronized power tard is used as an engine brake.

In this type of engine brake, the combustion injection is temporarily stopped at the time of a descent, etc., and opened and closed synchronously with the third valve at the end of the compression stroke of the piston to discharge the compressed air in the cylinder to the outside. Part of the energy required to compress the air in the cylinder can be used for braking.

[Problems to be solved by the invention]

However, such a power tard is effective as an engine brake at the time of descent, etc., because the pressure engine having high-pressure air of more than 20 kg / cm ² in the cylinder is released to the atmosphere as it is, If this pressure energy itself can be effectively used for braking, it can be said that it is very economical.

The present invention has been proposed in view of such circumstances,
It is an object of the present invention to provide an economical power tard device for a diesel vehicle that increases the engine braking force by utilizing the pressure energy of the high pressure air discharged from the third valve during the power tard operation.

[Means for solving the problem]

For this purpose, the present invention provides a four-cycle diesel vehicle that performs an engine braking action by opening the third valve for a short period of time synchronously at the end of the compression stroke of the piston and discharging the compressed air in the cylinder to the outside. An air tank that stores pressurized air and an air pressure governor that operates when the internal pressure of the air tank is equal to or higher than a predetermined value and that stops the supply of air to the air tank. When the air pressure governor is not operated, the third valve is used. The compressed air discharged is supplied to the air tank, and when the air pressure governor is operating, the compressed air discharged from the third valve is recirculated to the air supply manifold to increase the air pressure in the cylinder. It is characterized by doing.

[Action]

According to such a configuration, when the air pressure governor of the air tank pressurizing compressor is not operating during the operation of the power tard, the high-pressure air discharged from the third valve fills the air tank through the relay valve. When the air pressure governor of
It is introduced into the intake manifold via a relay valve.

As a result, the pressure in the compression stroke of the air in the cylinder at the time of power tard is further increased, and the braking energy of the engine brake by the power tard increases.

〔Example〕

Referring to the drawings, an embodiment of the present invention will be described with reference to the drawings. FIG. 1 is an overall system diagram, FIG. 2 and FIG. 3 are each a relay valve of FIG. 1, and FIG. FIG. 3 is a longitudinal sectional view showing a state when it is not in operation.

In the above figure, 1 is a non-turbo 4 cycle diesel engine having an intake pipe, an intake manifold 2, and an exhaust manifold 3, 4 is a plurality of cylinders of the engine 1,
Each cylinder head has an intake valve 2a and an exhaust valve 3
a and a third valve 5a for power tard are respectively provided.

6 is a free piston valve 6e in a valve housing having 4 ports
The port 6a is connected to the intake pipe 2 via the high-pressure air pipe 15, and the port 6b is connected to the third valve exhaust pipe 5
, The port 6c is connected to the downstream side of the air pressure governor 12 via the governor pipe 11c, and the port 6d is connected to the air tank 8 via the return valve 7 and the air charge pipe 17. I have.

Reference numeral 18 denotes an air tank charging compressor, the intake port of which is connected to the intake manifold 2 via a small-diameter intake pipe 13, the discharge port of which is connected to the air tank 8 via air charge pipes 9 and 17, and the governor pipe is connected to the air tank 8. Air downstream of the air pusher governor 12 provided via 11a is connected to a compressor unloader valve (not shown) provided in the compressor by a governor pipe 11b. Reference numeral 10 denotes an air pipe for guiding the air in the air tank 8 to an air brake, an air horn, and the like, and 14 denotes a relief valve of the air tank.

In such a structure, when the air tank pressure is equal to or lower than the set value, the air pressure governor 12 is inactive and the air pressure introduced into the port 6c of the relay valve 6 is zero. In the lower position shown in FIG. 2,
The high pressure air from the third valve 5a is supplied to the port 6b as shown by the arrow.
Through the port 6d to the air tank 8.

On the other hand, the compressor 18 is driven by the engine 1, draws air from the intake manifold 2 through the intake pipe 13, pressurizes the air, and supplies the compressed air to the air tank 8 through the air charge pipes 9 and 17. At this time, the air in the air charge pipe 17 does not flow into the relay valve 6 by the action of the recoil valve 7.

When the air pressure in the air tank 8 reaches a set value, the air pressure governor 12 is introduced, and a part of the downstream air is introduced into the compressor 18 through the governor pipe 11b, and the compressor 18 is actuated by an unloader valve (not shown). Air supply is stopped, and at the same time, air is introduced into the relay valve 6 downstream of the air pressure governor via the unloader pipe 11c and the port replacement 6c, and the free piston valve 6e is moved upward to the upper position shown in FIG.

Then, the high-pressure air from the third valve 5a flows from the port 6b of the relay valve 6 to the port 6a and is moved to the cylinder via the high-pressure air pipe 15 and the intake pipe 2, so that the cylinder internal pressure at the end of the compression stroke of the piston is extremely high. Since the large cylinder pressure is recirculated and introduced into the intake pipe via the third valve, the engine exhibits a very large power tard effect.

According to such a structure, the high-compressed air discharged from the third valve at the time of power tard acts as an engine brake as the power tard as before, but the discharged high-pressure air is recirculated to the intake pipe. Feedback is provided to further increase the cylinder internal pressure during power tard, thereby exerting a large braking effect.

[Effect of the invention]

In short, according to the present invention, in a four-cycle diesel vehicle in which the third valve is opened for a short time at the end of the compression stroke of the piston and the compressed air in the cylinder is discharged to the outside to perform the engine braking action. An air tank for storing pressurized air and an air pressure governor which is activated when the internal pressure of the air tank is equal to or higher than a predetermined value and stops the supply of air to the air tank. The compressed air discharged from the valve is supplied to the air tank, and when the air pressure governor is operating, the compressed air discharged from the third valve is recirculated to the intake manifold to reduce the air pressure in the cylinder. By raising it,
Even if the pressure energy of the high-pressure air cannot be recovered by the air tank, an economical power-tard device for a diesel vehicle that increases the engine braking force by using the pressure energy of the high-pressure air discharged from the third valve at the time of power-tard operation. Therefore, the present invention is extremely useful in industry.

[Brief description of the drawings]

FIG. 1 is an overall system diagram showing one embodiment of the present invention, FIG.
3 is the relay valve of FIG. 1, and FIG. 2 is the third valve when the air pressure gunana of the air tank is not operating.
The figure is a longitudinal sectional view showing a state during operation. 1 ... Engine, 2 ... Intake pipe (intake manifold), 2a
…… Intake valve, 3 …… Exhaust manifold, 3a …… Exhaust valve, 4…
... Cylinder, 5 ... Third valve exhaust pipe, 5a ... Third valve, 6 ...
Relay valve, 6a, 6b, 6c, 6d… Port, 6e… Free piston valve, 7… Non-return valve, 8… Air tank, 9… Air charge pipe, 10… Air pipe, 11a, 11b, 11c ... governor, 12 ... air pressure governor, 13 ... intake pipe, 14 ... relief valve, 15 ...
… High pressure air pipe, 17 …… Air charge pipe, 18 …… Compressor

Claims (1)

(57) [Scope of request for utility model registration] A third synchronously with the end of the compression stroke of the piston.
In a four-stroke diesel vehicle that opens the valve for a short time and discharges the compressed air in the cylinder to the outside to perform the engine braking action, the air tank that stores the pressurizing air and the internal pressure of the air tank are equal to or higher than a predetermined value. An air pressure governor that operates and stops the supply of air to the air tank. When the air pressure governor is not operated, the compressed air discharged from the third valve is supplied to the air tank, and the air pressure governor is A power tard device for a diesel vehicle, wherein when in operation, compressed air discharged from the third valve is recirculated to the intake manifold to increase the air pressure in the cylinder.